Nano multi-layered spherical quantum dot optimization by PSO algorithm: Maximizing the optical absorption coefficient

•We report a structure with maximum total absorption coefficient of 1.33×105m-1.•Optimal structure parameters are obtained by the PSO algorithm.•The refractive index changes are calculated based on the density matrix method.•The effects of pressure and temperature on the absorption coefficient are studied.•Sensitivity of the changes parameters on the results are checked numerically.

In this paper, the maximization of optical absorption coefficient of multi-layer spherical quantum dot (MSQD) has been investigated based on particle swarm optimization (PSO) method. By using this method and numerical solution of Schrödinger equation (energy eigenvalues and eigenvectors are calculated using the fourth-order Runge–Kutta method), optimal MSQD structure has been determined to maximise the optical absorption coefficient. Having introduced the optimal structure, the refractive index changes and effects of pressure and temperature on the optical absorption coefficient of this structure have been studied. The result shows that the maximum total optical absorption coefficient for the optimal structure is equal to 1.33×105m-1 and its sensitivity dependence to changes of the first well width is more than that of other parameters.